1. Field of the Invention
The present invention relates to the field of vacuum pulling device, and in particular to a hand/pneumatics dual operation vacuum pulling device, which can selectively operates as a pneumatic vacuum puller when pressurized air supply is available and can serve as a hand-operating vacuum puller when no pressurized air is available and still provide a strong suction and pulling force even operated by hands.
2. The Related Arts
A conventional dent puller for automobile metal sheet is commonly used to repair deformed metal sheet of a car. The conventional automobile metal sheet puller is generally classified as traditional hand-operating dent puller and later developed pneumatic dental puller. The traditional hand-operating automobile dent puller is rarely seen in the market due to a number of design defects. The pneumatic automobile dent puller is not easy to carry and use for it needs air compressor to generate a suction force and thus requires a constant supply of electrical power. The present inventor has proposed previously a “hand-operating vacuum pulling device” which is relatively advanced. Yet, a pneumatic puller is still of advantages in operation, even through it operation is limited by the supply of electrical power.
In view of the drawbacks of the “hand-operating vacuum pulling device” that was previously proposed by the present inventor and the known pneumatic dent pullers, it is desired to have a creative breakthrough in the technical field of dent puller or similar pulling devices in order to overcome those drawbacks.
Thus, the present invention aims to provide a novel pulling device with the purpose of eliminating the drawbacks of the known devices and providing a practical device.